Degree days for root, bulb and leafy vegetable pests – 15 August 2011

In Sarnia, the 3rd generation of cabbage maggot are expected to emerge in next day or so. In the London area, accumulated degree days have reached the threshold indicating the emergence of the 3rd generation of cabbage maggot. Also, in the London area, expect the 3rd generation of onion maggot to emerge in about 3-4 days.

Here are the degree days accumulated from April 1st until August 15th, 2011.

Area

Onion Maggot(base 4)

Cabbage Maggot(base 6)

Carrot Rust Fly (base 3)

Carrot Weevil (base 7)

Bradford/Holland Marsh*

1676.5

N/A

1808.3

N/A

Sarnia

1678.6

1435.8

1807.2

1320.6

London

1723.8

1474.7

1852.9

1353.4

Wellington

1499.5

1257.4

1624.3

1139.5

Windsor

1969.5

1710

2103.5

1587.6

Area

Tarnished Plant Bug (base 12)

Leafhopper (base 9)

GDD (base 5)

Bradford/Holland Marsh*

764.6

1075.5

1548.2

Sarnia

793.8

1098.6

1555.1

London

798.9

1119.9

1598

Wellington

620.7

917.1

1377.2

Windsor

1022.6

1352.5

1837.2

* Data provided thanks to Muck Crops Research Station, Department of Plant Agriculture, University of Guelph